#051212

CSS

:root {
  --black-stallion: #051212;
  --black-stallion-rgb: 5 18 18;
  --black-stallion-oklch: oklch(0.17 0.02 195.5);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(180 57% 5%);
  border-color: oklch(0.17 0.02 195.5);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #051212;
  --color-black-stallion-50: #eff7f7;
  --color-black-stallion-100: #e1eaea;
  --color-black-stallion-200: #cbd7d7;
  --color-black-stallion-300: #adbbbb;
  --color-black-stallion-400: #92a2a2;
  --color-black-stallion-500: #788a8a;
  --color-black-stallion-600: #667575;
  --color-black-stallion-700: #515e5e;
  --color-black-stallion-800: #3b4544;
  --color-black-stallion-900: #282f2f;
  --color-black-stallion-950: #161c1c;
}

SCSS

$black-stallion: #051212;
$black-stallion-rgb: 5, 18, 18;
$black-stallion-light: mix(#fff, $black-stallion, 20%);
$black-stallion-dark: mix(#000, $black-stallion, 20%);

.element {
  color: $black-stallion;
  box-shadow: 0 0 0 2px rgba($black-stallion, 0.35);
}